Here is the full list of all 28 8-Bit Invaders! achievements.
As a Galactic Marine Corp or Cranioids player, Win a skirmish (on hard or higher) or multiplayer game without building more than one additional harvester (the starting harvester doesn't count).
Find "Gwen" the penguin in each mission of the Galactic Marine Corp campaign.
Find "Gwen" the penguin in each mission of the Cranioid campaign.
Find "Gwen" the penguin in every mission of the 8-Bit Invaders solo campaigns.
Complete mission 6 of the Galactic Marine Corp campaign.
Complete the single-player campaign with the Galactic Marine Corp faction.
Complete the single-player campaign with the Galactic Marine Corp faction with at least 2 stars in each mission.
Complete the single-player campaign with the Galactic Marine Corp faction and earn all possible stars.
Complete the single-player campaign with the Galactic Marine Corp faction with every mission set to Hard difficulty.
Win a one-on-one skirmish game against an insane AI with the Galactic Marine Corp faction.
Complete mission 6 of the Cranioids campaign.
Complete the single-player campaign with the Cranioids faction.
Complete the single-player campaign with the Cranioids faction with at least 2 stars in each mission.
Complete the single-player campaign with the Cranioids faction and earn all possible stars.
Complete the single-player campaign with the Cranioids faction with every mission set to Hard difficulty.
Win a one-on-one skirmish game against an insane AI with the Cranioids faction.
Win a team multiplayer match against human players with a team consisting of at least one Galactic Marine Corp and one Cranioids player.
As a Galactic Marine Corp or Cranioids player, win a multiplayer match against human player playing a faction from one of the other 8-Bit games (Guardians, Renegades, Deathsworn or Lightbringers).
Complete all ten co-op campaign missions with at least one star.
Complete all ten co-op campaign missions with at least two stars.
Complete all ten co-op campaign missions and earn all possible stars.
Complete the following achievements: It's full of Stars!, Star Power, Getting Short, Inferior Species, Unlikely Allies, Galactic Team-Up, and Hexes are the Future.
Capture an unoccupied territory.
Capture an occupied territory.
Successfully defend a territory.
Win a Conquer the Metaverse game against an Insane AI.
Win an auto-resolved battle.
Win a battle and sustain no meta game losses.